Pension and Other Postretirement Plans (Tables)

3 Months Ended

Mar. 31, 2012

Components of Company's Net Periodic Benefit Cost

The following tables set forth the net periodic pension and postretirement benefit expense for Northern Trust’s U.S. and non-U.S. pension plans, supplemental pension plan, and other postretirement plan for the three months ended March 31, 2012 and 2011.

Net Periodic Pension Expense U.S. Plan	Three Months Ended March  31,
(In Millions)	2012			2011
Service Cost	$	8.8		$	10.7
Interest Cost		10.4			10.2
Expected Return on Plan Assets		(21.8	)		(19.7	)
Amortization
Net Loss		8.6			6.5
Prior Service Cost		(0.1	)		0.4
Net Periodic Pension Expense	$	5.9		$	8.1
Net Periodic Pension Expense Non U.S. Plans	Three Months Ended March 31,
(In Millions)	2012			2011
Service Cost	$	—		$	—
Interest Cost		1.6			1.6
Expected Return on Plan Assets		(1.6	)		(2.0	)
Net Loss Amortization		0.2			—
Gain on Curtailment of Non-U.S. Plan		—			—
Net Periodic Pension Expense (Benefit)	$	0.2		$	(0.4	)
Net Periodic Pension Expense Supplemental Plan	Three Months Ended March 31,
(In Millions)	2012			2011
Service Cost	$	0.7		$	0.8
Interest Cost		1.1			1.1
Amortization
Net Loss		1.5			1.4
Prior Service Cost		0.1			0.1
Net Periodic Pension Expense	$	3.4		$	3.4
Net Periodic Benefit Expense Other Postretirement Plan	Three Months Ended March 31,
(In Millions)	2012			2011
Service Cost	$	0.1		$	0.1
Interest Cost		0.4			0.7
Amortization
Net (Gain) Loss		(0.3	)		0.4
Prior Service Cost		(1.3	)		(1.3	)
Net Periodic Benefit	$	(1.1	)	$	(0.1	)